“Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?”
―
Carl Sagan

“I like the scientific spirit—the holding off, the being sure but not too sure, the willingness to surrender ideas when the evidence is against them: this is ultimately fine—it always keeps the way beyond open—always gives life, thought, affection, the whole man, a chance to try over again after a mistake—after a wrong guess.”
―
Walt Whitman,
Walt Whitman's Camden Conversations

“Men are never convinced of your reasons, of your sincerity, of the seriousness of your sufferings, except by your death. So long as you are alive, your case is doubtful; you have a right only to their skepticism.”
―
Albert Camus,
The Fall

“My desire and wish is that the things I start with should be so obvious that you wonder why I spend my time stating them. This is what I aim at because the point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it.”
―
Bertrand Russell,
The Philosophy of Logical Atomism

“The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what's true.”
―
Carl Sagan

“Tell a devout Christian that his wife is cheating on him, or that frozen yogurt can make a man invisible, and he is likely to require as much evidence as anyone else, and to be persuaded only to the extent that you give it. Tell him that the book he keeps by his bed was written by an invisible deity who will punish him with fire for eternity if he fails to accept its every incredible claim about the universe, and he seems to require no evidence what so ever.”
―
Sam Harris,
The End of Faith: Religion, Terror, and the Future of Reason

“One of the biggest problems with the world today is that we have large groups of people who will accept whatever they hear on the grapevine, just because it suits their worldview—not because it is actually true or because they have evidence to support it. The really striking thing is that it would not take much effort to establish validity in most of these cases… but people prefer reassurance to research.”
―
Neil deGrasse Tyson

“Moral certainty is always a sign of cultural inferiority. The more uncivilized the man, the surer he is that he knows precisely what is right and what is wrong. All human progress, even in morals, has been the work of men who have doubted the current moral values, not of men who have whooped them up and tried to enforce them. The truly civilized man is always skeptical and tolerant, in this field as in all others. His culture is based on "I am not too sure.”
―
H.L. Mencken

“Don't you believe in flying saucers, they ask me? Don't you believe in telepathy? — in ancient astronauts? — in the Bermuda triangle? — in life after death?No, I reply. No, no, no, no, and again no.One person recently, goaded into desperation by the litany of unrelieved negation, burst out "Don't you believe in anything?"Yes", I said. "I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I'll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be.”
―
Isaac Asimov

“If Jesus rose from the dead, then you have to accept all that he said; if he didn't rise from the dead, then why worry about any of what he said? The issue on which everything hangs is not whether or not you like his teaching but whether or not he rose from the dead.”
―
Timothy Keller,
The Reason for God: Belief in an Age of Skepticism

“I have always strenuously supported the right of every man to his own opinion, however different that opinion might be to mine. He who denies to another this right, makes a slave of himself to his present opinion, because he precludes himself the right of changing it.”
―
Thomas Paine,
The Age of Reason

“...What I have denied and what my reason compels me to deny, is the existence of a Being throned above us as a god, directing our mundane affairs in detail, regarding us as individuals, punishing us, rewarding us as human judges might.

When the churches learn to take this rational view of things, when they become true schools of ethics and stop teaching fables, they will be more effective than they are to-day... If they would turn all that ability to teaching this one thing – the fact that honesty is best, that selfishness and lies of any sort must surely fail to produce happiness – they would accomplish actual things. Religious faiths and creeds have greatly hampered our development. They have absorbed and wasted some fine intellects. That creeds are getting to be less and less important to the average mind with every passing year is a good sign, I think, although I do not wish to talk about what is commonly called theology.

The criticisms which have been hurled at me have not worried me. A man cannot control his beliefs. If he is honest in his frank expression of them, that is all that can in justice be required of him. Professor Thomson and a thousand others do not in the least agree with me. His criticism of me, as I read it, charged that because I doubted the soul’s immortality, or ‘personality,’ as he called it, my mind must be abnormal, ‘pathological,’ in other, words, diseased... I try to say exactly what I honestly believe to be the truth, and more than that no man can do. I honestly believe that creedists have built up a mighty structure of inaccuracy, based, curiously, on those fundamental truths which I, with every honest man, must not alone admit but earnestly acclaim.

I have been working on the same lines for many years. I have tried to go as far as possible toward the bottom of each subject I have studied. I have not reached my conclusions through study of traditions; I have reached them through the study of hard fact. I cannot see that unproved theories or sentiment should be permitted to have influence in the building of conviction upon matters so important. Science proves its theories or it rejects them. I have never seen the slightest scientific proof of the religious theories of heaven and hell, of future life for individuals, or of a personal God. I earnestly believe that I am right; I cannot help believing as I do... I cannot accept as final any theory which is not provable. The theories of the theologians cannot be proved. Proof, proof! That is what I always have been after; that is what my mind requires before it can accept a theory as fact. Some things are provable, some things disprovable, some things are doubtful. All the problems which perplex us, now, will, soon or late, be solved, and solved beyond a question through scientific investigation. The thing which most impresses me about theology is that it does not seem to be investigating. It seems to be asserting, merely, without actual study.

...Moral teaching is the thing we need most in this world, and many of these men could be great moral teachers if they would but give their whole time to it, and to scientific search for the rock-bottom truth, instead of wasting it upon expounding theories of theology which are not in the first place firmly based. What we need is search for fundamentals, not reiteration of traditions born in days when men knew even less than we do now.